Armor-piercing projectile.



No. 720,242. PATENTBD FEB. 10, 1903-. R. A. HADFIELD' ARMOR PIEROING PROJEGTILE.

APPLIOATIbN FILED NOV. 28, 189B.

H0 MODEL.

ATENT Orrrce.

ROBERT A. HADFIELD, OF SHEFFIELD, ENGLAND.

ARMOR-PIERCING PROJECTILE.

SPECIFICATION forming part of Letters Patent No. 720,242, dated February -10, 1903. Application filed November 23, 1898. Serial '0. 697,579. (No model.)

To all whom it may concern.-

Be it known th'at 1, ROBERT A. HADFIELD, a subject of the Queen of Great Britain, residing at Sheffield, county of York, England, have invented an Improvement in Armor- Piercing Projectiles, of which the following description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like'parts.

In order to increase the efficiency and penetrative efiect against metal plates, it has been common heretofore to apply caps to the end or head of projectiles, and various means have been devised for fastening the-cap upon the projectile. In one of the methods of fastening the cap to the projectile it has been proposed to groove or nick the head of the projectile and then apply the cap, which is .of softer metal and is forced or pressed onto the head of the projectile and partially into the groove or nick. This method of connecting the cap to the projectile is highly objectionable, for the reason that the groove or nick in the projectile considerably weakens the projectile in that portion where the shock or impact is first felt, resulting in a disintegration and breaking up of the projectile in many cases. In forming the nick or groove in the projectile in this old method of connecting the cap to the head of the projectile the tough outer skin of the projectile is often destroyed, and in any event the groove or nick presents a line or point of weakness in the very part of the projectile which should be strongest.

My present invention has for its object the production of a projectile not only free from the stated objections, but of such construction that the projectile is strengthened at its head or near its point by the means provided for securing the cap in-place, all as will here inafter more fully appear.

Figure 1 is a perspective view of a projectile and its cap detached, showing one mode of attaching the cap. Fig, 2, in side elevation, shows the capped projectile. Fig. 3 represents in elevation a projectile with a diflerout form of cap-attaching means, the cap being shown in section; and Fig. 4 is a similar view of yet another form of my invention.

In carrying out my invention I cast or forge in the rough a projectile which in its general shape may be of well-known or desiredform,

tacked.

as at P, Figs. 1 and 2, and in finishing the ogival or head portion P, I form on the exterior a retaining rib head, or lug, over which the cap C is subsequently pressed in any suitable manuer-as, for instance, by hydraulic pressure. This retaining-rib may be made in various forms, as herein shown. In Fig. 1 the retaining-rib b extends around the head portion in a plane at right angles to the longitudinal axis of the projectile and is made more abrupt or shouldered at its rear side at b than at its front side to facilitate setting the cap and also resist its accidental removal. To resist any tendency of the cap to turn, I remove or slightly recess the rib transversely thereto at one or more points, as at b to thus present depressions in or through the rib to be entered by a part of the metal of the cap to form a lock therefor against rotation. will be understood, the cap is preferably of softer metal than the projectile, and when it is applied to the latter it is' compressed behind the rib, asat c, Fig. 2, to frrmly and securely retain projectile and cap together as one.

It may be desirable in some instances to.

provide the projectile with, more than one re taining-rib, and in Fig. 4 I have shown the head portion P of the projectile as provided.

b making one or more turns around the head.

With this form'of retaining-rib it is not ab-* solutely necessary to attach the cap (1 in the first instance, for the correspondingly andim teriorly grooved cap could be screwed on as occasion might require, and the projectile could be fired with or without the cap, as deemed most desirable. For instance, in attacking soft armor the cap would probably be unnecessary or even objectionable, while, on the other hand, the cap could be quickly screwed on if hard-faced armor were being at- It is to be observed that the rib will be so made that the cap is preferably screwed into place in the direction opposite to the axial rotation imparted to the projectile by the riding of the 'gti-n'. If desirable, a small hole might be drilled in the cap at the end or" the spiral of largest diameter to receive a pin b riveted in place, which would form a lock to prevent unscrewing of the cap. While the spiral rib may be made sharper,it should preferably be made coarse and of sufficient crosssection to present a firm retaining portion for the cap.

In cast" projectiles the rib might be formed in the casting; but I prefer to machine it in order to secure a truer fit in the cap-groove.

The caps may be of any desired orsuitable form and material.

From the foregoing description it will be obvious that by my invention I notonly obviate the formation by cutting or otherwise of annular grooves in the projectile, but 1 ae tually strengthen the same where it is most necessary and desirable.

When spirally-ribbed projectiles are to be delivered already capped, I prefer to subject the, cap to pressure after it is screwed into place to thereby securely lock it against removal.

. Having described my invention, what I claim as new, and desire to' secure by Letters 'Patent, is-- hardened head provided with an integral external and also hardened retaining-rib, and a relatively soft malleable cap adapted to engage and be retained in place onthe head by pressure externally applied to the cap below or back of the rib.

8. A projectile having an external annular retaining-rib extended around the head portien therepf, and an interiorly-grooved cap adapted to fit over the head and be compressed behind the rib, the'latter entering the groove in the cap, and means to prevent rotation of the cap on the head.

4. An armor-piercing projectile having an annular rib on the head portion thereof, a cap adapted to engage and be retained in place on the projectile by said rib, and ,a locking-recess in and transverse tothe rib, to prevent rotation of the cap.

5. 'An armor-piercing projectile having a spiral rib on its head portion and extended from near the point thereof real-Warmly,- and a correspondingly interiorly grooved cap adapted to be screwed upon the projectile and retained thereupon by coeperation of the rib and groove, the inner surface of the'cap fitting snugly upon the external surface of the head portion of the projectile.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

R. A. HADFIELD.

"Witnesses:

GEO. H. HEMSOLL, E. MORTIMER. 

